The present invention is related to extracting power from moving fluids such as wind and water. Application examples include, but are not limited to, powering water pumps, process machinery and prime-mover dynamo plants having an integrated or external dynamo driven by a fluid current motor.
The supply of oil, natural gas, or coal, as resources for generation of energy is eventually limited, and will be too expensive to use for this purpose in the foreseeable future. In addition, the detrimental consequences of the combustion of oil, gas, and coal for the environment are sufficiently known.
The invention is designed to contribute to the protection of the environment, by using wind energy.
Wind turbines with a horizontal axis and a three-blade rotor have mostly outcompeted other known systems. However, these wind turbines also have disadvantages: if operated in the vicinity of populated areas, inhabitants are harassed by noise and shadows cast. In addition, equipment losses due to bird strikes have been reported. Modern wind turbines are under continuous demand for ever higher capacity. Higher capacity is achieved by extending the length of the rotor blades. Accordingly, the support tower has to be extended in length. The enlarged blades have more weight and a larger radius. This also strongly increases the centrifugal force. Correspondingly, the statics of the blade and load capacity of the pitch control have to be modified. A particular hazard for large wind power plants is lightning strikes. Cases are known where despite lightning protection systems, rotor blades have been struck by lightning and were destroyed. In other cases, the electric control was destroyed by lightning, or fire has destroyed the entire plant.
The highest degree of efficiency is achieved with a slender profile of the rotor blade. However, slenderness of profile in very large rotor blades is limited by statics. It is known that due to differences in wind speed, resonance oscillations may build up and lead to material fatigue. In the worst case, this can lead to physical contact of the blades with the tower and rupture of the blade. In addition, the passing of the blade at the tower creates objectionable noise and can, with both windward and leeward rotors, lead to resonance oscillations.
Wind turbine systems already exist that use sails, paddles, or blades that run in a continuous loop over chains, ropes, or belts, over two or four wheels. In these systems, sails, paddles, or blades are impinged with wind, setting the system to motion. In the Canadian patent specification CA 111 702 2 by Cocjin, a machine is shown in which wind paddles run in a chain drive orbiting around a base plate. Every wind paddle is additionally carried by two trolleys, which are orbiting supported by two u-shaped guide rails. The paddles run upwards impinged by the wind, and return protected from the wind by the shielding. Cojin's system has many disadvantages compared with the orbiting drum wind turbine of the present invention. One disadvantage is the chain drive. Additionally, the Magnus-Effect is not applicable in the context of Cocjin's construction principle. It is general knowledge that chains undergo material extension, create operational noise, and need extensive care. Moreover, Cocjin's machine cannot adjust to different wind velocities, because it lacks run control. As a consequence, the machine has to be shut off at higher wind velocities.